davidh4976 Posted June 13 Report Share Posted June 13 I’ve been dealing with getting glazes with Gerstley Borate, Custer Feldspar, etcetera converted to more available ingredients. I’ve run into hard panning on a number of the conversions and have had to add Bentonite. I’m also going to try reformulating to reduce reliance on Bentonite (only because it’s a little inconvenient to dry mix recipes that include Bentonite). I couldn’t find a whole lot of information on which ingredients cause hard panning. A low amount of clay is reportedly a significant contributor. Nepheline Syenite is a reportedly a significant contributor to hard panning. But, what else? So, while mixing some glazes, I took the opportunity to do a test. I set aside 50 grams each of individual ingredients in individual jars and added 80 grams of water and let them set. I monitored them over time to see which ones hard pan on their own. Here are my results: Nepheline Syenite hard panned within an hour. The rest of the ingredients listed below took a couple of weeks to be able to judge how they hard panned, if at all. All of the following feldspars hard panned within 1 week: Mahavar, Custer, G-200 EU, Minspar 200. Silica 325 hard panned within 1 week The following Ferro frits were semi-hard panned. They were quite stiff but I could stir them up with a little effort. They were about “half as hard panned” as Nepheline Syenite. Ferro Frits 3124, 3134, 3195, and 3249 Ferro Frit 3110 had some minimal stiffness at 2 weeks and was easily stirred. OM-4 Ball Clay and EPK were happily and fully suspended at 2 weeks. Whether this is beneficial or helpful, I don’t know! Photo of the lab included. 😊 Callie Beller Diesel, Kelly in AK and Min 3 Quote Link to comment Share on other sites More sharing options...
Mark C. Posted June 13 Report Share Posted June 13 (edited) Nepheline Syenite is used in cone 6 glazes and is a known hard panner as well as any frit as it's ground glass and is basically small rocks. The cure for all settling glazes is Magma. It a game changer for any glaze that settles hard Yes you will need to learn how it thickens the glaze and slows the drying a bit but its just a learning curve Edited June 14 by Mark C. Babs, PeterH and Rae Reich 3 Quote Link to comment Share on other sites More sharing options...
Kelly in AK Posted June 13 Report Share Posted June 13 That’s cool! Thank you for sharing. Quote Link to comment Share on other sites More sharing options...
PeterH Posted June 14 Report Share Posted June 14 A little more detail and a tiny cautionary note. https://shop.brackers.com/magma-miracle-anti-gravity-multipurpose-additive/ MAGMA will dramatically thicken any glaze it is added to. Thinning the glaze to a “normal” consistency will cause very thin coats. MAGMA containing glazes must have more viscosity than typical glazes. MAGMA glazes also take more time to “dry” (the water moves into the bisque slower) after dipping or spraying. If high viscosity glazes will not work for you, and/or slow setting or drying glazes will not work for you, you should not use MAGMA. Quote Link to comment Share on other sites More sharing options...
Bill Kielb Posted June 14 Report Share Posted June 14 (edited) 14 hours ago, davidh4976 said: A low amount of clay is reportedly a significant contributor Yep, clay is the suspender so usually at least 10% or more clay to reasonably suspend in a recipe. Neph Sy has minimal silica and alumina comparatively so what better way to lower melting requirements before boron was a thing. Many always try and have 10-20% clay in their designs to suspend everything else. Glaze Calc helps make this a bit easier these days. Boron, a game changer to use other materials. Edited June 14 by Bill Kielb Rae Reich, Callie Beller Diesel and Kelly in AK 3 Quote Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted Tuesday at 04:42 PM Report Share Posted Tuesday at 04:42 PM I’ve reformulated a few gerstley borate glazes successfully at this point, and some general things I’ve found: -if a GB glaze has little or no clay in it, using frit 3134 for boron and calcium, neph sye for some alumina and the sodium, and epk or other clay for the additional alumina needed will give you a glaze that settles less. Frit 3134 has a lot less alumina for the specific purpose of being able to up the clay content in a glaze to help keep it suspended. -you may still need to use a little supersaturated epsom salt solution to keep the glaze suspended, but that does work a treat. Some gerstley borate glazes can be prone to slow drying anyways, so you may not notice a big difference in that area. -you may find some crawling or spitting issues with layered glazes resolve, especially if the glaze had more than 20% GB. Bill Kielb, Kelly in AK and Hulk 3 Quote Link to comment Share on other sites More sharing options...
oldlady Posted yesterday at 02:13 AM Report Share Posted yesterday at 02:13 AM try making the glaze in distilled water. i have such hard water that if i leave any in a container long enough for it to dry out, i can easily pick up some that resembles a potato chip, we measure all the ingredients carefully but hard water has calcium (and lord knows what else) that changes the balance. results? Quote Link to comment Share on other sites More sharing options...
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